ABSTRACTS APPARATUS AND LABORATORY PRACTICE AND DEMONSTRATIONS The Synthesis of Urea from Carbon Monoxide and Ammonia. P. RISCBIETH. 2. physik. chem. Unterricht, 42, 212-3 (Sept.-Oct., 1929).-Wdhler's synthesis of urea can be demonstrated in a two-hour period. (See: P. RISCHBIETH. "Quantitative Chemische Versuche," Hamburg, 1929, p. 96,) The svnthesis from carbon monoxide and ammonia can be shown also in the same length of time. A dry gas buret (I) is filled with chlorine preoared oure from notassinm nerkangahate and hydrochi& acid. Another buret (11) is filled
.
~~~
Ir
buret filled with chlorine is placed in the sunlight and cannected t o the other buret by a short piece of mbber tubing. Both sto~cocksare onened and all the &bon monoxide is passed into the first buret (I) containing chlorine by simply lifting 111. After a few minutes all the carbon monoxide has passed into the first buret and the color of chlorine has disappeared. The stopcocks are closed and the buret containing the products of the reaction is turned upside down several times in order to facilitate the mixing. Then 2 4 cc. of concentrated ammonium hydroxide are introduced through a gas buret. The final solution containing ammonium chlorideand urea is evaporated to dryness on the water-bath and the urea is extracted with absolute alcohol. It can then be tested for with the standard tests. The following equations represent the reactions which took place:
+ + + +
co CIS COCI, COCL 2NHs +CO(NH& 2HC1, 2HC1 2NHs +2NH4C1 Approximate quantitative results can be obtained by treating the solutim with ammonium oxalatr ar.d cooling. Cry~t;~lline, white w e n monoxalatc [CO~Kllp)2.11.C20,] 3recinitatrs out and a n be filtered od. dned. and w i u h r d The f rllawine examulc !how; typical results obtained in such an emeriment. 100 cc. C1. f 100 cc. CO 1U0/765 mm. dry 94.5 cc. CIS 94.5 CC. co 0°/760 mm. dry 0.299 g. C12 0.127 g. CO 0.426 g. Phosgene 60 Urea: Theoretical quantity X - = 0.258 g. 99 21 Urea oxalate: Theoretical quantity X - = 0.451 g. 12 Urea oxalate found 0.31 g. The discrepancy found is due chiefly to the fact t h a t urea monoxalate is slightly roluble. L. S. Combined Mercury Seal Stirrer and Reflm Condenser. T. L. KELLY. Homae, 3,103 (Oct., 1929).-"A Fisher bromination tube (E & A No.32708), which has a side u m A far the reflux condenser, is fitted with a rubber stopper B fitting tightly around 5 e outside of the bromination tube. A piece of wide glass tubing Cis fitted tightly over 187
+
-
+ +
~
~
-
.~~
188
JOURNAL OF CHEMICAL EDUCATION
'
JANUARY,
1930
the rubber stopper B. The stirring rod D is now fitted with a rubber stopper E, having a piece of glass tubing H fitting tightly over the stopper E. This is the sealing tube which revolves with.the stirring rod and which must dip well below the surface of the mercury, which is in the well formed by the glass tube C. The brominatiou tube easily fits c into a narrow-necked flask by means of a stopper. "This device has been used successfully in this laboratory in the preparation of small amounts of II compounds prepared by the Fittig, Friedel-Crafts and Gattermann reactions, as one can readily pour a liquid into the reaction flask through the mouth of the reflux condenser." D. C. L. AutomaticFilter. R. W. ASHWORTH. Chem.Anolyst, 18, 17 (July 1, 1929).-In the diagram i t will be noted that tube 1 does not quite extend through the stopper into the flask A. Tube 2 extends almost to the bottom of A and in the funnel B t o within cm. of the end of I. When the liquid in B falls below end of 2 a slight liquid head, sufficient to start the flow from A, will be formed in 1. As B fills, the end of 2 becomes submerged, cutting off the air supply displacing the liquid in A , thus stopping the flow. If i t is desired to separate a heavy suspension from the liquid, 1 may be adjusted to extend into A . Then, as the suspension falls down'the sides of the flask itwill collect and build up a ound the exit tube 1 , instead of going down into the funnel and clogging up the paper. D. C. L. Automatic Filter. L. G. DAKE. Chew?.-Analyst,18, 18 (July 1, 1929).-To avoid having a rubber stopper in contact wlth the solution being filtered the author recommends the use of a glassstoppered separatory funnel. The diagram is self-explanatory. After the solution has been filtered the separatory funnel may be filled with distilled water and the precipitate washed. Few precipitates are coarse enough t o clog up the stopcock and besides the weight of the liquid in the funnel forces the precipitate through D. C. L. continuously. Design and Construction of Efficient Laboratow Air-Pressure A NJ. B. MULL. Chem.-A1~dy~l, 18, Filter. H. L. K A ~ ~ MAND 20-1 (Sept. 1, 1929).-Detailed description for construction with four diagrams. D. C. L. A Simple Hydrogen Sulfide Generator. 0. A. CROSBY. Chem.-Analyst, 18, 17 (July 1, 1929).-The apparatus required far the H.S generator suggested includes: two rubber stoppers, small quantity of glass wool, a retort receiving flask, short piece of rubber tubing, and some glass tubing. Glass wool is inserted a t the neck on the f l a k and is used as a retainer for the ferroussulfide at A. A solid rubber stopper is inserted a t the mouth of the neck t o retain the FeS
VOL.7, No. 1
ABSTRACTS
189
and a small one-hole rubber stopper with a short piece of glass tubing is inserted a t the opening D, This serves as the lead-off for the H a . Dilute HCI is kept in reserve a t C. To operate merely lower the neck of the flask and the acid runs in through the glass wool to the FeS. When through using raise the neck so that the acid drains into the bowl and there will he no waste of gas or materials. The advantages claimed for this generator are: (1) more efficient than the Kipp: (2) cost is small-81-65 as compared to %I2for a Kipp; (3) can be set up a t convenient places in the laboratory; (4) can be set into a chalk box or similar container and take up very little room. D. C. L. Automatic Siphon-Filter Device. A. VonHIES, JR. Chem.-Analyst, 18, 18 (Nov. 1, 1929).-"The accompanying drawing shows a way of combining siphon action and filtration in a manner that is perfectly automatic and self-regulating. The siphon may be started by blowing into a rubber tube temporarily slipped over the end of air-tube a. Once the liquid begins t o pour into the funnel through liquid tube 6, the rubber tube is removed from the end of tube a. If the liquid filters slowly the funnel will fill by siphon action until the level of the bottom of tube a is reached. Automatically the siphon ceases t o work. Further filtration then lowers the level in the funnel below the opening of tube a, and siphon action is once more resumed until the bottom of tube n is again sealed with liquid. "This arrangement can of course be extended touse with a Buchner funnel for suction filtration!' D. C. L. A Safe, Convenient Method for Transferring GasMeasuring Tubes. R. E. DUNBAR.Chem.-Analyst, 18, 15 (July 1,1929).-An ordihary 3/,-inch iron or brass deflegrating spoon wlth 15-inch handlerfrom which the bend has been removed, slipped over the end of the tube, while under water, is recommended for transferring gas-measuring tubes from one vessel to another. D. C. L. A Non-Splash Bottle. J. C. BAU. Chm.Analyst, 18, 18 (July 1, 1929).-The wash bottle recommended differs from the ordinary one in having the outlet tube somewhat larger and fitted a t the lower end with a Bunsen valve inside the tube. I n the drawing, A is the lower end of the delivery tube made somewhat smaller a t the hottom. B is a rubber tube inside the glass tube which is turned back over the lower end of the glass. C C C are slits in the rubber tube for the passage of the water. D is a short piece of glass rod to dose the end of the rubber tube. I t is better to have several short slits in the D. C. L. rubber tube than one long one. Small Laboratory Hydrogen Sulfide Outlet W. A. BACAE. Chen.-Analyst, 18, 16 (July 1, 19291.-It is recommended that the liquid through which the H B is t o be passed be placed in an Erlenmeyer flask fitted with a rubber stopper, provided with inlet and outlet tubes. The latter is connected with a long rubber tube which passes out of the window t o a point about a foot below the sill. D. C. L. An Improved Pipet. H. JAMBS. Chem.-Analyst, 18, 18 (Sept. 1, 1929).-"A pipet which will give excellent service can be made from apiece of glass tubing which has an internal diameter of aboutr4 mm. Hold the glass tube vertically with one end in a hot flame. Thelend will soon fuse
190
JOURNAL OF CHEMICAL EDUCATION
JANUARY,
1930
shut. Rotate the tube in the flame until a drop of glass begins t o form on the end, then allow the tuhe t o cool. Break off the drop-like end a t the proper place and smooth offthe tip thus formed with emery cloth. The resulting pipet has a fine point with a very thick wall." D. C. L. An Improved "Steamin -Out9'Device. J. CORNOG. Chem.-Analyst, 18, 17 (Sept. 1, 1929).-"%he funnel part of the device here pictured was obtained by cutting the bottom from a 250-cc. Erlenmeyer flask. The cross-hatched areas represent rubber stoppers. The narrow parallel lines represent 6 mm. glass tubes. "If water is placed in the flask and boiled, the steam passes out only through the straight tube, because the lower end of the curved one is submerged. The steam passing through the straight tube may he used to "steam out" a beaker or other hollow apparatus inverted over the opening. Much of the condensate falls into the funnel and is periodically siphoned hack into the flask whenever the water in the funnel rises above the curved tuhe. Vesselsmay he steamed continuously for hours without the addition of more water to the flask." D. C. I,. Prevention of Flask Bumping during Boiling. H. I,. SKINNER. Ck.-Analyst, 18, 8 (Sept I, 1929).-The author proposes the addition of a little hydrogen perox~de,m such cases where the slight oxidizing (or reducing) action would not interfere with the process. The slow liberation of oxygen furnishes nuclei for the formation of steam bubbles and humping is prevented much more effectively than with the commonly used glass beads. This method has the disadvantage that the hydrogen peroxide soondecomposes and must be renewed from time to time. D. C. L. A Practical Use for Broken Funnel Tubes: Base for Test Tubes. 0. A. CROSBY. Chem.-Analyst, 18,21 (Sept. 1. 1929).-With file, cut broken funnel a t a p e and m o t h edge with w e gauze. Anneal glass and while the glass is soft make a flange by using a file or pointed piece of metal (Figure 1). If i t is desired to have the test tube permanently attached to this base, heat both to n yellow heat and weld (Figure 2). This base is practical for it is not easily tipped over. D. C. I,. ----A Hydrofluoric Acid Boxes Used for Microscope Camera. H. SPURRIER. Chem.-Analyst, 18, 16 (Sept. 1.1929).The adaptation of two hydrofluoric acid boxes for a successful microscope camera is described in detail. D. C. L. .. Elechic Cutter for Glass Tubing and Bottles. R. B. WAILES. Chem-Andyst. 18, 23 (Sept. 1, 1929).-Details given for making an electric cutter for large-diameter tubing. D. C. L. To Prevent Loss of Stoppers in Stopcocks. C. E. RONNEBERG.Chen.-Analyst, 18, 16 (Nov. 1, 1929).-To replace the customarily used string or rubber band used in an attempt to keep ground glass stoppers with their original seats the author suggests the use of fine brass chain, known t o hardware trade as "single jack brass chainfiNo.21, D. C. L. for burets and a coarser chain, No. 18, far reagent bottles. Reclamation of Silver from Residues. I,. C. CASE. Chem.-Analyst, 18, 14 (July 1, 1929).-"Dissolve the silver chloride residues in strong ammonia, then add a saturated solution of sodium hydrosnlfite until no more precipitate forms. This precipitate is composed of fine flakes of silver. Filter and wash in a large Goo& crucible. Pour concentrated nitric acid through the filter until the precipitate dissolves. The filtrate is evaporated to dryness and baked for two hours at 110' to eliminate excess acid. The dry salt may be weighed and made up t o desired strength. Filtration of these solutions D. C. L. is generally necessary before stsndardization." Prevention of Overtitration. A. H. MOODY. Chem.-Analyst, 18, 11 (Sept. 1, 1929); cf. Tms J O U ~ N A L , 6, 797 (Apr., 1929).-"Into the titrating flask or beaker is placed a glass tuhe of suitable size to hold the de$red quantity of reserved solution being titrated. The top of the tube is fitted with a short length of rubber tubing with at-
VOL.7, No. 1
ABSTRACTS
191
tached pinch cock, clamp, stopcock, or preferably glass bead valve. At the beginning of the titration part of the solution is drawn up into the tube and held by closing the pinch cock. "When the main body of the solution has been titrated the pinch cock is opened, the rubber tubim removed and the tube rinsed with distilled water both inside and out and l~ then remured The titrltion is then e ~ r d u lmmplctcd. "Thr mrthud is of 5pecial servire when an o~rtshlcindicator is hring used, s a v i n ~the added work- of a n extra tttratior~urdinxrilv used todctrrmine thc anon~ximateend-ooint. ~Sufficient solution ~ r e & v e d t o e x c e e d the last added increment'& titratiua solution." I). C. L. A More Efficient Method of heparing Molgbdate Reagent for Phosphorus Pentoxidc Determinations. J. CONMAK.Chem-Anolyrl. 18, 7 ( S o v 1. 10?!l).- To nrrvent ''cakitld' WIICII the conccntratrd ammonium hvdroxrdc solution is added to the molybdic acid sispension, rapidly whirl the latter with stirring rod during the addition. Thcaurhur prcpnrcq 12-litcr rolumcs of this $elution acccrdirlg tu these ;lirwtims and rncuuntrr< no difficdty with the solution of thc molybdie a c d D.C. I,. A Book Suonort for the Chemical Laboratorv. XI. G . M ~ X L O NSrh . Sci.3 M d h . . 29, 72830 (02.; 1929); see THISJOURNAL, 6, i 6 2 fJan.. 1929).-Illustration and de: scription of a device to hold laboratory manual while in use in 1abo;atory so as to save time, economize on space, and prevent damage to manual. B. H. B. ~
~~
~~
~
>
~~
~~~~
~
~~.
~
~
a
TEACHING OBJECTIVES, METHODS, AND SUGGESTIONS; CURRICULA Supervised Study in Chemistry. B. F. LAMONT. High-Sch. Tencher, 5, 282 (Oct., 1929).-Reading is of prime importance in any method of study. The supervised study period offers opportunities t o the teacher to improve the method of reading on the part of the student. I n order to learn the student must first comprehend, which involves the power of visualizing the material read and of interpreting i t from personal experience. A scicnce depends on the laboratory. to a large degree, far a suitable background of experience. Chemistry necessitates the learning of a new vocabulary; frequent vocabulary drills then are an aid to the student in grasping such material. Training in reading with a definite purpose, and getting a t the key points of a sentence and paragraph rapidly are essentials to successful study. Finally, i t is helpful to summarize, and to review. The author has suggested the following devices which have proved helpful t o him: 1. Alwaysmake a clear conciseassignment of thenewlesson. Motivate it, and teach students bow to attack the new problem. ? 2. Overcome the student's reluctance to search beyond the textbook far information. Have reference works near a t hand. 3. Give a ward of encouragement t o the faithful pupil and of censure or warning t o the poor pupil. 4. Habituate pupils t o drill themselves; it is not amiss t o teach them the laws of habit formation. 5. Teach proper methods of memorizing. 6. Give frequent diagnostic tests; point out t o weak pupils their specificweaknesses in chemistry. 7. During the supervised study period take your weak pupils and review and drill them to overcome their weaknesses. 8. Try t o make the subject matter meet the needs of the individual pupils. Give maximum, average, and minimum assignments. 9. Furnish your pupils with a list of good study habits. 10. Give training in good methods of silent reading. A number of good exercises are H. T . B. suggested for this purpose. Balancing Chemical Equations. W. H. HAMMOND. Chem.-Andyst, 18, 14 (Nov. 1,1929).-A general method is suggested employing elementary algebra for the balancing of any chemical equation, however difficult. D. C. L. The Elements of the Last Series of the Periodic Table. Omo HAT 2.angm. Chem., 42, 9 2 4 9 (Sept. 14, 1929).-The last horizontal series of the periodic table is very incomplete. Mast of its 32 members are unknown. Three reasons have been suggested why this series ends with uranium, element No. 92. 1. V. M. Goldschmidt ("GeochemiscbeVerteilungsgesetze der Elemente," 11,1924, p. 23) considers the possibility that there are higher members of this series, perhaps the homologs of the platinum metals, namely, elements Nos. 94-96. These elements exist only vety sparingly or not a t all a t the surface of the globe but may occur to a much larger extent as siderophile elements in the iron-nickel center of the earth. Gold-
JOURNAL OF CHEMICAL EDUCATION
JANUARY,
1930
schmidt distinguishes between siderophile, chalcophile, and litophile elements according to whether they occur essentially in the iron-nickel center of the earth, or the higher sulfide melt, or in the silicate melt below the surface. According to Goldschmidt, elements with the atomic numbers 119 and higher are litophile. Their existence is very questionable. If he be correct about the existence of these elements, then elements Nos. 9 4 9 6 should possibly he found in certain platinum ores a t the earth's surface. So far there is no experimental support for this theory. 2. Other reasons for the absence of the elements above uranium are based on theinstability of the arrangement of their atoms. I t has been proposed [S. Rosseland, Nature, 111,357 (1923); W . Kossel, Naturu.,16,298 (1923)l that in thecase of these elements, the electrons of the most central electron orbit or of the highly elliptical orbits of higher levels come so close t o the inner kernel that they attract each other, fall into the kernel, and thus decrease the charge. 3. E. Rutherford IProc. Roy. Soc., London, 123,373 (1929)l suggests aparticular in-
his exp&ments that the aver& mass of the hel&m particles in the elements of atomic weights between 120 and 200 is about 4.005 while i t is4.011 for ordinary, doubly charged helium. From the equivalents between mass and energy i t foflows that a helium particle with a mass larger than that of the ordinary particle has a higher energy value. If such a helium particle should suddenly appear as ordinary helium outside of the kernel then i t must have lost in mass while energy was liberated. From the atomic weight 200 on, the energy content of the kernel increases very rapidly. Therefore uranium and thorium disintegrate voluntarily with the evolution of energy. Hence, itisvery possible that on account of the increase in mass of the helium particles the higher elements hecome so unstable that they are not capable any more d existence. From the frequency of the elements in this series, the author reasons that radium is not the only representative of element No, 88 but that there should he another inactive or very little active eka-barium which may occur in the earth's crust independently from uranium and thorium. Experiments to isolate this element 10. HAHN ANDK.DOUST, Z. Phys. Chem., 139,143 (1928)l from 220 kg. of barium bromide prepared from witherite were unsuccessful. From the negative results of the spectroscopic determinations i t can be calculated that the concentration of the inactive isotope of radium in this mineral Any further search for this element seems t o be is certainly not more than 2 X futile as it can hardly be expected that any other mineral contains itinlarger quantities. As this search for s stable or slightly active &-barium was unsuccessful i t seems probable that the chances are very slight for the existence of primary elements with odd atomic numbers in the last series of the periodic table. Therefore, if the elements ekatantalum, eka-lanthanum, and eka-caesium exist a t all, they must be extremely rare. Hence it follows that uranium and thorium are the only known independent elemeutsof the last series of the Periodic Table. There is little hope t o find any others. The author discusses also eka-caesium, protactinium, and actinouran, the probable L. S. source of the protactinium series. The New Periodic Tahle and Atomic Structure. I. W. D. HACKH. Chem. Neus. 139, 275-8 (Nov. 1, 1929).-A chart with a detailed description of the proposed arrangement. The elements are divided into Divisions A and B, the difference between these two being that all elements belonging t o the former differ only by the electron arrangement of one, namely the outermost shell or orbit; while the elements of the latter ,. D. C. I involve the electron arrangements of two (or three) shells or orbits. Data on Reagents. C. J. SCHOLLENBERGER. Ckem.-Analyst, 18, 8 (Nov. 1, 1929);-Time reauired for calculations mav he saved bv haneina in a convenient place in th; laboratow'a chart containing comm&ly needed infor&ti& on various reagents. . of conc rrnuent, grams artive Such data would rncludc molrcul;u weixln, average ~ pgr. iny-rsdicnt per ml rlclrmd!fgof cuncn reagent, m . crnc. rcagent prr litrr frr normal 1). C. L ~ ~ l u t i o ml n . t., dilute ,700 for usc as dilute rrncents (3' N . E. Asroc. ~ o k Aspects e of Chemical Equilibrium. 'G. H. B u ~ ~ o w sRept. . Chenz. Teachers,31, 8-12 (Sept., 1929) -The chemical equation tells how much of a desired substance may be gained, only in case the reaction ontinues to completion, and if no side products are formed. It is most helpful t o look upon equilibrium as the state of things when two opposing chances have become of eoual velocitv. h e n the tempera& is raised; equilibrium is shifted in the direction that is ac0.C. companied by absorption of heat.
.
VOL.7, NO. 1
ABSTRACTS
193
0. J. MCGAPBIGAN. of work of hlgh-school pupils in testing samples of ink from school supply houses and other sources. Other pupils manufactured ink from various formulas. Aqua ammonia sold in the grocery store for house use has been analyzed. Also vine0. C. gar, milk, ice cream, and gasoline. The Excursion Project. 11. F. F. GAITHER. Educ. Screen, 8, 230-1 (Oct., 1929).-In a preceding article [see THISJOURNAL, 6, 1361 (July-Aug., 1929)], the author discussed some characteristics of the excursion project; in this paper he conmders ways and means of initiating and carrying forward such a project. Attent!o? is given to ways of making sure that the choice of project is that of the pupils; that it 1s usable in the school'slocality, and that the teacher has definite suggestions t o follow in planning B. C. H. for the enterprise once it has been decided t o embark upon it. Visual Methods in Science Teaching: H. C. MCKAY. Educ. Screen, 8, 196-200 (Sept., 1929).-This paper tells m some detail how the amateur may make his own photomicro-films. Specifications are given for the type of microscape, beam splitter, B. C. H. camera, lamp, and supports. The Use of Moving Pichues in the Teaching of Certain School Subjects. T. M. CARTER. P l i Delta Kappas, 12, 7 6 4 (Oct., 1929).-Starting with some principles of psychology basic in analyzing moving pictures for their promise in serving educational ends, the author proceeds to apply those principles to such school subjects as: geography, history, zotil?gy, agriculture, and technical subjects. Same of the prmciples enumerated are: (1) the mobility of the image hinders the perception of form. (2) Moving images give better notions of relative and of group movements than of individual movements. (3) If farm is the element of instruction that is being emphasized, the slide is better than the movie. (4) Verbal instruction should precede rather than follow the visual aid. The author frankly admits that "we have dealt more withlimitations and shortcomings of the moving picture than with the possibilities which it possesses." B. C. H. Shall Laboratory Work in the Public Schools Be Curtailed? W. C. CROXTON. Sch. Sci. & Malh., 29, 730-3 (Oct., 1929j.-Reply t o a m t s l s m made concerning an article which suggests that adequate data are not yet available upon which t o base recommendations for substituting lecture demonstrations for other forms of laboratory B.H. R . procedure involving a greater amount of student *me. How Develop a Useful School Library. T. F. TYLER. Ne6. Educ. J,,9 , 472 (Sept., 1929j.-A superintendent of a small school tells hgw, with a few banks as a start, he has built up a library of over seven hundred volumes which serves not only the school hut the community as well. The clerical work for the library is handled by high-school girls who are trained by the superintendent and the retiring librarian. The local Woman's Club has been active, in the community referred to, in providing funds and helping to choose books for the library. A state traveling library is a regular visitor in that community. B. C. H. Recent Developments in Cuniculum-Making in Denver. A. K. LOOMIS. Progr. Educ., 6 , 2 6 2 3 (Sept.-0ct.-Nov., 1929).-The present program in curriculum-making in Denver began in the school year 192223. The first round of revision was practically completed in 1928, the results of which are published in monograph number twelve. During the second semester 1927-28 seven hundred fifty classroom teachers coeperated in the appraisal of thirty-four new courses of study, and a thorough program of testing wasused in measuring pupil achievement under the new courses. Work is now under way looking t o the complete analysis of the specific objective of education in the Denver Schools. The newer courses of study emphasize the broader concepts, attitudes, and understandings which give purpose t o the more easily measurable knowledge and skills. The results of the testing program seem to indicate that increased emphasis on the broader concepts, attitudes, and understandings has resulted in no less efficientwork in C. M. P. the skill and knowledge objectives. The New Course of Study ~ !i. Science of New York City. EDIT. School, 51, 112 (Oct. 17. 1929).-Some qualities which this course exhibits put in the words of Superintendent O'Shea are: " It stresses items which occur most frequently; i t stimulates experimentation; i t recognizes practical teaching problems by adjusting time allotments,. . .(and) by providing for the "slow" as well as the "bright child.. . . . Stressing, as i t does, the experimental approach, the new course.. .(seeks t o develop) that most important objective of science instruction. . . the scientific habit of mind." It is suggested that the boy or girl, who has truly caught thescientificattitude toward the appliances which the ingenuity of our scientists has placed a t his disposal, better Association of Chemistry with a Few Practical Problems.
Rept. N. E . Assoc. Ckem Teachers, 31,13-7 (Sept., 1929).-Tells
.
..
194
JOURNAL OF CHEMICAL EDUCATION
. JANUARY, 1930
understands the same spirit in Lindbergh when he speaks of himself and his plane as "We." B. C. H. KEEPING UP WITH CHEMISTRY Particle Size and the Properties of Matter. H. A. NEVILLE. ~ h e m . - ~ n a l ~18, sl, 4-5 (Sept. 1,1929); 4-5 (Nov. 1,1929).-The way in which the sizeof particlemay modify considerably the properties of either naturally occurring or artificially produced substances is brought out in these two articles. The variations of such properties as solubility, color, sedimentation, vapor pressure, density, and chemical activity with particle size and the significance of these relations are briefly discussed. D. C. L. Vanadium and Some of Its Industrial Applications. J. ALEXANDER. Chcm. & Ind., 48, 871-8 (Sept. 6, 11)29) and 895:901 (Sept. 13, 1929).-Vanadium, named by SefstrBm m honor of Vanadls, the Scandmavian goddess of youth and love, was really discovered by a Mexican in 1801 who called it erythromium. The chemistry of vanadium is as complex as the chemistry of carbon. The principal uses of the metal a t the present time are, as a catalyst, in ferrous and non-ferrous metallurgy, in pharmacy and therapeutics, in agriculture, photography, and in the manufacture of glass. A classified bibliography of over 200 references is appended. E. R. W. The Possible Use of Beryllium in Aircraft Construction. H. W. GILLETT. Can. Chem. & Met., 13,276 (Oct., 1929).-Some study of light allbys consisting primarily of beryllium is needed before this metal can be classed as an actual material for aircraft construction. D. C. L. The Production and Uses of Beryllium. K.ILLIG.Chem. Age (Mo. Met. Sect.), 21, 17-8 (Sept. 7, 1929).-Beryllium is prepared by the electrolysis of a fused mixture of sodium-beryllium fluoride and barium-beryllium fluoride, a t a temperature above 1300°C. Pure beryllium is a coarsely crystalline metal, brittle and hard enough to scratch glass. It may be alloyed with other metals; the alloys with aluminum, copper, nickel, cobalt, and silver have been briefly studied. The heat treatment and electrical conductivity of some alloys are discussed. 2. R.W. Basic Industrial Minerals: No. 8. Ultramarine. G. M. DYSON. Chem. Age, 31,255-6 (Sept. 21,1929).-This article treats of the occurrence, the color and structure, and the synthesis of ultramarine. E. R.W. Lime Process for Coating Aluminum. L. M c C a ~ o c n . Can. Chem. & Met., 13, 271 (Oct., 1929).-A brief discussion of the process and description of coatings produced. D. C. L. Thermal Efficiencies of Aluminum Saucepans. C. LANDRETH AND MRS. R. 0 . HuTcnrNsoN. I. Home Economics, 21, 5 9 9 4 0 4 (Aug., 1929).-Relative efficienciesof light and heavy aluminum ware were determined by (1) rate of heating, (2) retention of heat, (3) proportion of water evaporated during cooking process, (4) durability, and (5) cost. As results of this study i t may be assumed that (1) the thermal efficiencies of light and heavy cooking utensils are the samc. (2) The loss of water by evaporationisafunetion of the fit of the lid and not the thickness of the wall. (3) The difference in cost between well-constructed light and heavy aluminum ware can only be justified on the grounds of greater durability. R. A. B. Nickel Mesh in the Radio Grid Tube. C. C. C o ~ s u . Inco, 9, 10-1 (1929).A radio tube which was only brought out this year, but which has become one of the most important of the line, is known as the UY-224. The outer grid of the UY-224 is one of its most distinctive features, as only two other tubes possess such an element. Nickel is used in making this mesh largely because the Monel which was used in earlier tubes would not stand the high temperatures necessary to drive the gases fully from the metal during tube evacuation. Other properties which render nickel acceptable for this use are; its pliability, its immunity to tarnish, its high melting point, its ease of B. C. H. spot-welding, and its high purity a t reasonable cost. Rich Mineral Deposits Await Development in Algeria. J. BRUSSET. Explosives Engineer, 7, 217-23 (June, 1929).-Algeria is characterized by the fact that she bas no coal depos~tsand no gas-oil. Only a very narrow ship of the coast is really in contact with the outside world. The Atlas mountains are highly mineralized but practically unexploited. Up to the present the whole of the mines production is exported-consisting chiefly of iron ore and phosphate rock. High-grade zinc and lead ore are now being mined also. Distance, lack of men, and lack of powerpresentthethreemajordifficulties. Hydroelectric power is being rapidly developed. The article is profusely illustrated. R. A. B. Metal Spraying. L. PESSEL. Chem.-Andyst, 18, P 5 (July 1, 1929).-The metallurgical and chemical aspects of the process of metal spraying are summarized as follows:
VOL. 7, NO. 1
ABSTRACTS
195
"Any metal obtainable in wire can be sprayed. The spraying tool, weighing three pounds, contains a feeding mechanism, driven by compressed air, which feeds the metal wire automatically toward the tip of a nozzle, where it is molten by an oxygen-acetylene flame. As soon as a d r o of ~ metal forms. i t is instantlv atomized bv camnressed air and impacted upon the surf& t o be coated: Metal coafings can thus be formed on practically every surface, provided it is clean. Sandblasting has proved t o be the best preparation of the surface." These metal coatings can he built up t o any desired thickness, from 1/1000th of an inch up to an inch or more. The most irnpurutnt rnrtsls which have been successfully sprayed arezinc, cadmium. nluminum, r n a g w s w n , tm, icad. cupprr, nickrl, irm, stlinlew .;tecl, .\Ionel, bnmrc. hracs. and German a1vr.r. Comments on each. indudinc aJvantnuc;and disndwntuucs. " are included in this short article. D. C. I;. ' Some New Carbon Blacks. W. B. W ~ O A N D .C m . Chen. & Mel., 13, 269-70 (Oct., 1929).-Some new varieties of carbon black are described which are claimed to be purer than the old ones. This purification has, contrary t o experience with "adsorptive" carbons, been combined with a reduced, instead of increased, adsorptive activity. D. C. L. Recent Advances in the Low-Temperature Preservation of Foodstuffs. T . MORAN. Chem. & Ind., 48,245T-51T (Aug. 23, 1929).-Living foodstuffs (fruits and vegetables) have different optimum temperatures for storage, due probably to the different temperature coefficients of the chemical reactions which predominate in the living system. Results of researches on several fruits are given. With dead foodstuffs (animal products) the most favorable temperature has been found to be 3638°F. The principal functions of low temperature here are (1) to slow dawn the action of molds, (2) controlling the extent of structural change in tissues during freezing and thawing. The control of humidity is very important, a high relative humidity permitting the spoiling of food, even in the frozen state, by mold. E. R. W. Influence of Heat upon Water Absorption of Certain Dried Fruits. H. B. TROMPSON AND G. C. BURK. I.Home Economics. 21, 593-8 (Aug.. I929).-Since the cooking properties of dried fruits depend upon the absorption of a large part of the water lost in the previous desiccation, the authors studied the conditions which promote such absorption [see A. W. KNAPP,"The Drying of Vegetables," 5.Soc. Chenz. I d , 45, 123-8 (1926)l. The authors found that long soakingincold water is not an aid in thecooking of dried apples, apricots, figs, and prunes (the only ones tested). rImmersion in hot water (80"bailing) for a short time results in maximum water absorpbon, favors a shorter cooking period and yields a superior product. R. A. B. Tung Oil. L. A. JORDAN. Chem. & Ind., 48, 847-55 (Aug. 30,1929).-Tung oil is an essential raw material in varnish manufacture. At present China controls the world's supply, although i t has been shown that it may be successfully produced in the United States. A bibliography of over 150 references is included. E. R. W. Industrial Water. ANON. Silicate P's & Q's, 9, 1-2 (Tenth Month, 1929).Water 98% pure is not attractive to one who is informed in such matters. New York City's water is99.995'%ppureand still is "hard" enough to be objectionable far industrial purposes. It is estmated that the soap wastage in softening water that may be but 99.97'70 pure became of hardness would amount to about $100.00 per day for a city of 40,000 people. Since the benefits of soft water are felt by everyindividualusingitsoftwateriscoming to be considered a strong civic asset. City after city is giving thought t o softening its water. South Orange, New Jersey, is one city which has made a water-softening installation. Over 900,000 gallons of water are passed through the three Doucil softeners per day. This softening unit does its work so well that hard water actually has t o be added, after the softening, to raise the hardness to the standard, 26 parts per million, which has been found to do least damage by corrosion. B. C. H. Cyanamid, Its Uses a s a Fertilizer Material. F. E. ALLISON. Chem. News, 139, 199-201 (Sept. 27, 1929).-A briei discussion of the manufacture and properties of cyanamid. Fertilizer practices in Europe and the United States, transformations in the soil, and cyanamid in mixed fertilizers are other topics discussed. M. W. G. Early Chemical Processes in Rayon Production. Chem. News, 139, 212 (Oct. 4,1929).-It is noted that the chemical methods originally employed for coagulation and finishing of the yarn are with minor modifications now employed for the production of "cellophane or transparent paper." M. W. G. 300 Miles to the Gallon. W. G. SEEPRAW. Colliers, 84, 10 (Oct. 5. 1929).-
-
196
JOURNAL OF CHEMICAL EDUCATION
JANUARY, 1930
Experts have stated that there are only nine billion barrels of oil in the earth and that ten vears will see the end of i t a t the oresent rate of use. This. however. does not worm the motor car manufacturer and need not worry the user. Over four timesmore gasnlinr puwrr is hein):ol,tainrd fromcrudr oil than fifteen years ago. .4ll automobile engincs are bcmg wnstructcd so as to give more mileage. Still mom imorovemcnt
